The present invention relates to a system for producing tires.
In the road vehicle tire manufacturing industry, forming devices are used to produce green components. These green components are processed and assembled to form green tires, which are then cured in respective molds.
To produce tires according to given specifications, the green components coming off the respective forming devices are normally on-line quality tested to make sure the respective mixes are as required, i.e. are such as to impart the desired physical characteristics to the respective components. And, as it is processed and fed to a tire assembly machine, each component is normally also subjected to various on-line checks, such as: identification checks to identify and make sure the right component is being supplied; quality control to ensure the component has the desired physical characteristics (elasticity, hardness, etc.); dimensional inspection to make sure the shape and size of the component and/or the shape, size and location of part of the component are as required; and structural inspection to ensure the desired distribution of the material (no porosity, etc.) within the component.
Despite all the above checks, however, some tires, even when formed from components individually within the acceptance range, are still found to fall short of the desired characteristics, thus lowering the average quality of the tires produced. Moreover, recent research shows a marked increase in the problem as regards the electrical conductivity of the tires, owing to the tendency to use less carbon black in the manufacture of tires.
What the art needs is a tire production system designed to eliminate the aforementioned drawbacks, and which, in particular, is cheap and easy to implement.
According to the present invention, there is provided a tire production system for producing tires with a toroidal carcass, a tread and defined internally by two annular beads. The system includes a production line for assembling the tires and a control station located at the end of the production line for taking on-line measurements of the electrical conductivity of each tire.
The present invention also relates to a tire production method for measuring the conductivity of a tire. The tire includes a toroidal carcass having a tread and defined internally by two annular beads. The tire is fed to a control station and placed into a start position. The beads of the tire are engaged by two opposing gripping bodies which move the tire into a measuring position by a combined first movement of the gripping bodies. The control station then makes a conductivity measurement of the tire while the tire is in the measuring position.